Driving means for spinning machines



July 19, 1938. E. A. GREEN DRIVING MEANS FOR SPINNING MACHINES Fi-ledJune 16, 1957 Inventor: Edward A.Gr-een y d/za/. His Attorney.

Patented July 19, 1938 I UNlTED STATES PATENT OFFICE Edward A. Green,Schenectady, N. Y., assignor to General Electric Company, a corporationof New York Application June 16, 1937, Serial No. 148,487

7 Claims.

My invention relates to driving means for spinning machines and thelike, more particularly to driving means in which each spindle is drivenby a separate motor, and has for its 5 object a simple and reliablesystem for starting and stopping the spindle motors in synchronism witheach other and in a predetermined proportionate speed relation withdrivin means for the other parts of the spinning ma- 10 chine.

In the operation of spinning machines wherein the spindles are driven byseparate high-speed motors and wherein the feeding means and othermechanism, such as the ring rail, are driven 15 by a low-speed motor inthe conventional manner it has been found that when the spindle motorsand the feed driving motor are de-energized to stop the machine, themotors do not decelerate in synchronism, i. e., in adesired timerelation or at the same proportionate rate. The spindle motors tend tocoast for a longer period of time with the result that the yarn istwisted excessively between the bobbin and feed rolls.

. This is detrimental to the yarn and results in 25 a length of yarn ofinferior quality on the bobbin when the machine is shut down when thebobbins are only partly filled. Moreover, the excessively twistedportion often results in breakage of the yarn when the machine isstarted.

30 In accordance with my invention I provide a main low-speedlow-frequency driving motor which is large enough to drive the completemachine, but which is mechanically connected to drive directly onlythose parts ofthe machine 35 other than the spindles such as the feedingmeans and the ring rail. For energization of the separate high-speedspindle motors I provide a high frequency generator which is driven fromthe main driving motor, together with suitable switching means forenergizing the field of the generator when the main driving motor isenergized, for maintaining the excitation of the generator during thedecelerating period, and increasing it at the beginning of theacceleration and the completion of the deceleration. Thus the spindlemotors are electrically locked with the generator during accelerationand de-' celeration and during deceleration may be re- 50 generativelybraked through the generator in the event that they do not decelerate asfast as the main driving motor.

For a more complete understanding of my invention reference should behad to the accom- 55 panying drawing the single figure of which isa abledirect current source of supply 28.

diagrammatic representation of a driving system for spinning machinesembodying my invention.

Referring to the drawing, for purposes of simplicity and clarity theelements of the spinning machine essential to an understanding of the 5invention only have been shown. It will be understood that my inventionis applicable to any spinning machine and the like with separate drivingmotors for the spindles, including machines in which there is no draftmechanism, sometimes known as twisting machines. The spinning machinecomprises suitable feed and draft mechanism ill for feeding theuntwisted yarn from the bobbin Ii to the bobbin M on the spindle l3, asuitable ring rail mechanism It being provided for simultaneouslyeffecting the twisting and feeding of the yarn to the bobbin in aconventional manner. It will be understood that the machine consists ofa plurality of feeding bobbins ii, and spinning bobbins i2, perhapsseveral hundred, with suitable feeding mechanism. Each bobbin i2 isdriven by a separate individual high-frequency high-speed motor I!having a speed on the order of 6,000 to 12,000 R. P. M. so that themotor can be connected directly to its spindle.

In accordance with my invention I provide a main driving motor l6 ofsufliclent size to drive the entire machine including the spindles II.This motor, however, is connected to drive directly through gearing I1and shaft IS the feed and various other mechanism of the machine but notthe spindles I3. For the operation of the spindles I provide a generatorI9, having a normal high frequency, such as 180 cycles, which isconnected through suitable gearing 20 to the main driving motor It. Thespindle motors I! are connected in parallel relation to each other tothe high frequency generator IS. The speed of the generator I9 and henceits frequency and the speed of the spindle motors it: may be varied bysuitably varying the ratio of the gearing 20.

The main driving motor i6 is preferably a suitable three-phase motor ofstandard frequency such as a three-phase 60 cycle squirrel cageinduction motor. It may be connected by means of an electromagneticswitch 2| to a suitable three-phase supply source 22, the coil 23 of theswitch being controlled by suitablemeans such as push buttons 2! and 25.

For the control of the field of the generator it I have provided anelectromagnetic switch "for connecting the field circuit 21 to a suit-The coil 2! of this switch is controlled by a contact and closedsimultaneously with the switch 2|.

Therefore, when the switch 28 is closed by closing the button 24, whichis preferably provided with suitable means for holding it closed, theswitch 28 is closed and field energization applied to the generatorwhereby the voltage oi the generator gradually buildsup as the speed ofthe generator increases with the speed of the motor 96. Consequently thespindle motors is are accelerated in a predetermined proportionate speedrelation with the main driving motor 6%.

Preferably the spindle motors it are three-phase high-torque squirrelcage induction motors which accelerate in synchronism with the increasein frequency of the generator.

When it is desired to stop the machine the button 25 is depressed tode-energize the coil 23, the button 2 3 being thereupon opened.Preferably a suitable time delay mechanism such as a dashpot Si isprovided for the switch 26 so that it is held closed, after thede-energization of its coil it, during the decelerating period. 0rsuitable timing mechanism maybe provided for delaying thede-energization of the coil 29 for a predetermined interval after theopening of the contact 863. Thus during deceleration the spindle motorsit are electrically locked to the generator is which in turn ismechanically locked to the driving motor 96. This assures decelerationof the motors together, In case the spindle motors tend to decelerate ata proportionately slower rate than the driving motor they act asgenerators supplying power to the generator it which then acts as amotor and tends to drive or prevent deceleration of the motor it.

To further assure the electrical interlocking of the spindle motors withthe generator W at low speeds and low frequencies during both theacceleration and deceleration, I have provided a centrifugalspeed-responsive device 82 which is driven by the motor 96 and operatesa pivoted switch arm 83. At low speeds this switch arm as shown inthedrawing closes a circuit around a resistance 34, in the field circuitof the generator 89. This provides for increased excitation of thegenerator at low speeds. At a predetermined high speed the centrifugaldevice moves the arm 33 to open the circuit around the resistance 36thereby inserting the remittance in the field circuit and decreasing thefield to its normal value.

In accordance with the provisions of the patent statutes, I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent thebest embodiment thereof,but I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent oi the UnitedStates is:.

l. A driving system for spinning machines and the like provided withyarn feeding means and. individual spindle motors, comprising a maindriving motor for said feeding means, a generator provided with a fieldcircuit and connected to be driven by said main driving motor,electrical connections between said generator and said spindle motors,main switching means for controlling the energization of saidmaindriving motor, and field switching means in said field circuitcontrolled by said main switching means to energize the field of saidgenerator whereby said spindle motors are started and accelerated withsaid main drivi motor. .r

2. A driving system for spinning machines and the like provided withyarn feeding means and individual high-speed spindle motors, comprisinga main driving motor for said feeding means, a high-frequency generatorprovided with a field circuit and connected to be driven by said maindriving motor, electrical connections between said generator and saidfeed motors, main switching means for controlling the energization ofsaid main driving motor, field switching means in said field circuitoperated by said main switching means to energize the field of saidgenerator simultaneously with the energization of said main drivingmotor whereby said spindle motors are started simultaneously with saidmain driving motor, and means responsive to the speed of said generatorfor increasing the field excitation of said generator during low speedoperation of said generator.

3. A driving system for spinning machines and the like provided withyarn feeding means and individual spindle motors, comprising a maindriving motor for said feeding means, a generator provided with a fieldcircuit and connected to be driven by said main driving motor,electrical connections between said generator and said spindle motors,switching means for energizing-said main driving motor and said fieldcircuit whereby said spindle motors are started with said main drivingmotor, and means for maintaining the field circuit of said generatorenergized after deenergization of said main driving motor until saidmain motor and said spindle motors have come to rest.

4. A driving system for spinning machines and the like provided withyarn feeding means and individual spindle motors, comprising a maindriving motor for said feeding means, a generator provided with a fieldcircuit and connected to be driven by said main driving motor,electrical connections between said generator and said spindle motors,main switching means for controlling the energization of said maindriving motor, field switching means in said field circuit controlled bysaid main switching means to energize the field of said generatorwhereby said spindle motors are started and accelerated with said maindriving motor, and means for maintaining the field circuit of saidgenerator closed after operation of said main switching means todeenergize said main driving motor until said main motor and saidspindle motors have come to rest, whereby said spindle motors and saidmain motor are decelerated in a predetermined proportionate speedrelation with each other.

5. A driving system for spinning machines and the like provided withyarn feeding means and individual high-speed spindle motors, comprisinga main driving motor for said feeding means, a high-frequency generatorprovided with a field circuit and connected to be driven by said maindriving motor, electrical connections between said generator and saidfeed motors, main switching means for controlling the energization ofsaid main driving motor, field switching means in said field circuitoperated by said main switching means to energize the field of saidgenerator simultaneously with the energization of said main drivingmotor whereby said spindle motors are started simultaneously with saidmain driving motor, means controlling said field switching means tomaintain the field circuit of said gen crater energized afterdeenergization of said main driving motor until said main motor and saidspindle motors have come to rest, whereby said spindle motors and saidmain motor are decelerated in a predetermined proportionate speedrelation with each other, and means responsive to the speed of saidgenerator for increasing the field excitation of said generator duringlow speed operation.

6. A driving system for spinning machines and the like provided withyarn feeding means and individual highspeed spindle motors, comprising amain driving motor connected to drive said feeding means, ahigh-frequency generator provided with a field circuit and connected tobe driven by said main driving motor, electrical connections betweensaid generator and said spindle motors, main switching means forcontrolling-the energization of said main driving motor, field switchingmeans in said field circuit operated to closed'position by said mainswitching means to energize the field of said generator simultaneouslywith the closure of said main switching means to energize said maindriving motor whereby said spindle motors are started and accelerated ina predetermined proportionate speed relation with said main drivingmotor, and means for maintaining said field switching means closed for apredetermined time interval after the opening of said main switchingmeans for deenergization of said main driving motor thereby to maintainfield energization of said generator until said main motor and saidspindle motors have come to rest, whereby said spindle motors and saidmain motor are decelerated in a predetermined proportionate speedrelation with each other.

'7. A driving system for spinning machines and the like provided withyarn feeding means and with the closure of said main switching means toenergize said main driving motor whereby said spindle motors are startedand accelerated in a predetermined proportionate speed relation withsaid main driving motor, means for maintaining said field switchingmeans closed for a predetermined time interval after the opening of saidmain switching means for deenergization of said main driving motorthereby to maintain field energization of said generator until said mainmotor and said spindle motors have come to rest, whereby said spindlemotors and said main motor are decelerated in a predeterminedproportionate speed relation with each other, and means responsive tothe speed of said generator for increasing the excitation of saidgenerator during low-speed operation of said generator.

EDWARD A. GREEN.

